Which of the following substances would make better permanent magnets?
Ferromagnetic materials
Ferrimagnetic materials
Diamagnetic materials
Paramagnetic materials
Ferromagnetic materials have higher curie temperature than other types of magnetic materials.
Basically, in ferromagnetic materials, metals ions randomly oriented in small regions known as domains. When a magnetic field is applied on these domains, they get oriented in the direction of the magnetic field and thus these materials become permanent magnets.
Option (a) is correct